In <9709208773.AA877394921(a)compsci.powertech.co.uk>uk>, on 10/20/97
at 05:47 PM, Philip.Belben(a)powertech.co.uk said:
Are you _sure_ the ABC was electronic? I was under the
impression that
the 1930s machines were all (almost all?) relay computers. Konrad Zuse
is the pioneer whose name is oft mentioned here...
Thanks for your response.
The ABC was definitely electronic. Vacuum tubes were used as part of
the calculation logic, and capaciters were part of the memory (combined in
a mechanical rotating drum). Many concepts used for the first time are
still in use in modern machines, although with significantly different
technology.
I have found a web site with some information, at:
http://www.sci.ameslab.gov/ABC
The ABC was certainly not a general purpose machine, and I couldn't
find information on how it was programmed. It did use a card reader and
punch for input and output.
The patent case showed that the Eniac used concepts from the ABC, and
invalidated Speery's attempt to collect royalties from the other large
manufacturers.
According to the web site, the memory was 30 words of 50 bits each.
This was apparently similar to the Manchester prototype.
Harlan
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Harlan Warden, near Van Cleve Iowa
hdwarden(a)netins.net
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